Fluid storage mixing and dispensing containers



A1181 22, Wm H. R. KNiTTEL ETAL 3,337,039

FLUID STORAGE MIXING AND DISPENSING CONTAINERS Filed May 27, 1963 2Sheets-Sheet l INVENTORS RICHARD R. KNITTEL WALTER H. SMAROOK ATTORNEYAugzz, 1967 Filed May 1963 R. R. KNITTEL ETAL 3,337,039 FLUID STORAGEMIXING AND DISPENSING CONTAINERS 2 Sheets-Sheet 2 INVENTORS RICHARD R.KNITTEL WALTER H.3MAROOK ATTORNEY United States Patent Smaroolr,Corpora- This invention relates to the mixing and dispensing of fluidsand more particularly to a container assembly for mixing fluids such asepoxy resins and their hardeners and for dispensing the mixture.

With the increasing popularity of fluids which must be stored separatelyand then mixed just prior to use, as for example, epoxy resins and theirhardeners, containers capable of the separate storage of fluids and thesubsequent dispensing of the fluids, have increased in importance.

The general acceptance and the widespread use of these containers hasbeen greatly hampered by the fact that in many applications one or moreof the fluids are toxic, caustic, or otherwise hazardous to handle. Forexample, in the case of plumbing seals employing an epoxy resin mixedwith a toxic amine hardener, the artisan who is to use the mixture, mustbe provided with premeasured quantities of the epoxy resin and hardenersafely stored in separate containers, and must be provided with safe asWell as simple means for first thoroughly mixing the resin and hardenerand then dispensing the mixture at pressures up to 80 pounds per squareinch (p.s.i.) or more, from caulking guns such as disclosed in US.Patents 2,838,210 or 3,042,268.

Containers which employ internally positioned pistons, for mixing and/ordispensing, present considerable personnel hazard during the step ofopening the container for insertion of the piston. The prevention ofleakage around a piston, particularly, during high pressure operations,requires the use of complex, expensive seals. The close tolerancesrequired between moving parts in order to prevent leakage result infrictional resistances which increases with increasing operatingpressures and increasing viscosity and can make the equipmentimpractical to operate.

Containers which consist of one flexible container within anotherflexible container have been employed for the separate storage offluids. Mixing is normally accomplished by applying pressure to theouter container, thereby causing a frangible seal on the inner containerto break, and permitting the mixing of the separately stored fluids.These types of containers are not readily adaptable for use indispensing guns, employ a kneading type of mixing operation which doesnot provide for the adequate mixing of viscous fluids, and run the riskof premature breakage of the frangible seal and the consequent prematuremixing of the separately stored ingredients.

It has now been found that fluids can be stored in separate containerswhich are readily axially compressible and provide not only for theconvenient and thorough mixing of fluids, but also are adapted for usein dispensing guns having pistons which function externally of thecontainers thereby permitting the containers to be completely sealed,other than at the dispensing outlet.

According to the present invention a compressible container for thedispensing first rigid section and a second flexible section. The firstand said second sections are preferably conical in configuration and incombination form an enclosed hollow chamber. At least one of saidsections has in association therewith, a scalable means for ingress andegress of fluid. The flexible section is foldable Within said rigid offluids is provided, having a v section in order to substantiallycompletely displace fluid from said chamber and through the egressmeans.

Advantageously, each of the sections have radially decreasingdimensions, with increasing distance from the central zone of thecontainer.

A further aspect of the present invention comprises a pair of theaforementioned containers in fluid tight engagement. The interiorchambers of said containers are in communication and form a fluid-tightbinary mixing container assembly, in which two fluids can be mixed byalternately compressing one container and then the other.

Other objects and advantages of the invention will be appreciated andthe invention will be better understood from the following specificationwherein the invention is described by reference to the embodimentsillustrated in the accompanying drawings wherein:

FIGURE 1 is a side elevational view of a pair of mated containers,

FIGURE 2 is a side elevational view, partly in section, of a modifiedcontainer,

FIGURE 3 is a fragmentary, section, and

FIGURE 4 is a fragmentary, side elevation, in section, of a modificationof the containers of FIGURE 1.

The structure of the present invention includes basically a pair ofresiliently flexible containers 10 and 11 which are employed in a matedarrangement. The containers must be capable of being repeatedlycompressed and expanded to at least their uncompressed size. Thematerial of the containers is, therefore, preferably a resilientpolymeric material as, for example, a polyolefin such as polyethylene orpolypropylene, flexible olefin copolymers such as poly(ethylene-ethylacrylate), rubbery materials such as polybutadiene and butyl rubbers,isoprene polymers, natural rubber, plasticized vinyl resins or the like.The particular material of construction is not critical in thisinvention.

The material of the containers should be substantially inert to thecontents of the containers or at least lined with an inert coatingmaterial. In the use of containers for the storage and subsequent mixingof an epoxy resin or complex epoxides and a hardener, low densitypolyethylene, preferably coated with a permeation resistant coating,gives the desired degree of flexibility, resiliency, inertness andimpermeability.

Each of the containers 10 and 11 has a rigid section 12 and 13 and aflexible section 14 and 15. The containers are compressed by foldingover the flexible section until it completely inverts and fills theinterior of the rigid section.

A cylindrical configuration provides maximum internal volume for a givenlength and diameter, and cylindrical sections made from a high rubberymaterial, particular when thin walled, can be repeated inverted withoutcracking. Advantageously, because of their greater ease of folding andtheir ability to be used with thick walls which are capable ofwithstanding high internal pressures. As shown in FIGURE 2, thecontainer capacity can be increased While maintaining a constantcontainer diameter, through the use of a container 21, having anelongated cylindrical section 22, between the rigid and flexible conicalsections 23 and 24, respectively.

The container units can be formed into the desired shape and size by anyconvenient method, such as by slush molding, powder fusion, blowmolding, centrifugal casting or the like. I

The blow-molding process is preferred for the manufacture of thecontainers because of the low cost'of mold and the rapidity and accuracyof the process. The blowside elevation, partly in of a parison ofvarying cross-section and a mold,

conical sections can be employed molding process is also preferablebecause of the ability of the blow-molding process to yield wallthicknesses which decrease with increasing distances from the centralaxis of the container.

Therefore, the rigid section of the container will have decreasingrigidity with increasing distance from the central axis, while theflexible section will correspondingly have decreasing rigidity orincreasing flexibility with increasing distance from the central axis.

It should be noted that the terms rigid and flexible as employed herein,and in the appended claims, are intended to indicate the ability of onesection to resist substantial deflection while the other section isbeing pressed against it, thus decreasing the internal volume of thecontainer and causing fluid to flow therefrom. The relative differencesin rigidity may be obtained through any desired means, such as by havingdifferent wall thicknesses in the two sections or by any other means, asfor example, the use of a rigid support device which has a contoursubstantially the same as that of one section. Thus, even a containerhaving two flexible, thin walled sections of equal thickness can ineffect, have one relatively rigid section through the use of an externalsupport device and one relatively flexible section.

The flexibility of the flexible sections 14 and 15 can advantageously,be further enhanced through the use of a plurality of axially displaced,circular, parallel grooves 16 and 17, however they are not critical andessential in the flexible section. They are however, highly desirable,and preferably are present. These grooves serve to increase the areaover which plastic must be distributed, and therefore, decrease thethickness of the plastic. The flexibility, and correspondingly, the easeof inverting a grooved conical member is determined by the stiffness ofthe material in the wall of the cone, as well as the number and siZe ofthe grooves and the amount of clearance maintained between groovesduring the folding operation.

For proper clearance between adjacent grooves, the maximum diameter ofeach groove should be less than the minimum diameter of the next largergroove, and preferably, the difference in diameters should be at leastequal to the depth of a groove.

The maximum diameter of a groove, such as groove 17 of container 11, asshown in FIGURE 1, is at the lower edge 19, of the groove. The loweredge of the groove is at the point of contact of the groove and the wallof the conical, flexible section 15. The minimum diameter of a groovesuch as 17', is at the peak 20 of the groove. The peak of a groove is atthe point of tangency of a line tangent to the groove and parallel tothe central axis of the container. The depth of a groove is equal to thediflerence between the maximum and minimum diameters of the groove.

The difference between the maximum diameter of one groove and theminimum diameter of the next larger groove increases with increases inthe distance between grooves and the vertex angle of the grooved conicalsection and decreases with increases in the depth of the grooves.

The vertex angles of the conical sections, in order to providesufficient clearance between grooves during folding should be at least40 and preferably no less than 60, while in order to provide foradequate internal volume of the containers with reasonable diameters,the vertex angles should not be greater than 140 and preferably shouldbe less than 120. The use of 90 vertex angles is thus seen to produce adesirable compromise between groove displacement and container capacity.

Inasmuch as the flexible section is to be inverted, and folded againstthe rigid section, the vertex angle of the flexible section must be noless than the vertex angle of the rigid section, and the distance fromthe center of the container to the apex or truncated base of theflexible section must be no greater than the distance from the center ofthe container to the apex or truncated base of the rigid section. Thus,in a container, such as container 4.- 21, the distance from the centerof the container (the mid-point of section 22) to the base of neck 26,should be no greater than the distance from the center of the containerto the base of the spout 2.7, and the vertex angle of section 24 shouldbe slightly less than the vertex angle of section 23.

It should be noted that excessive differences between the lengths orvertex angles of the rigid and flexible sec-' tion prevent the flexiblesection from coming into flush contact with the rigid section. Theresultant space between the inverted flexible section and the rigidsection causes waste by preventing complete emptying of the containerduring the dispensing operation.

It has been found that the use of equal container lengths and about a 6difference in vertex angles of the flexible and rigid sections providesfor proper emptying of a container. The truncated base of the rigidsection will thus be somewhat larger than the truncated base of theflexible section and will permit firm contact between the two bases.

It also should be noted that the grooves produce annular pockets betweenan inverted flexible section and the rigid section and, therefore, thegroove depth should be kept small in order to minimize waste.

The wall thickness of articles produced by blow molding can be variablyregulated through the use of a parison having varying thickness. The useof non-uniform parisons is in accordance with well known techniques, asseen for example, in United States Patent 3,084,395.

As shown in FIGURE 3, the parison 30, has a thick section 32 and arelatively thin section 34. Obviously, the thick portion of the parisonwill form the rigid container section while the thin portion of theparison will form the flexible container section.

The use of a multi-thickness parison and/ or an undulating or groovesurface yields a substantial difference in structural strength betweenthe two sections 46 and 48 and assures the easy and uniform inverting ofone section into the other.

The operation of the containers is not significantly influenced byhaving either the flexible section 24, adjacent to the neck portion 26of the container as shown in FIG- URE 2, or having the rigid section 12,adjacent the neck section 18, of container 10, as shown in FIGURE 1.

FIGURE 4, shows a container which was made in accordance with thetechnique shown in FIGURE 3. The application of a force F, on thecontainer 40, causes the container to yield initially at the weakestportion of the container, the outermost portion of the flexible section46. The collapsing continues radially inward until the flexible section46 is completed inverted and in contact with the inner surface of therigid section 48.

In a container, such as container 21, as shown in FIG- URE 2, employinga conical section in combination with a cylindrical section, the foldingwill normally occur initially in the region where the conical sectionmeets the cylindrical. Depending upon the relative stiffness of theconical and cylindrical sections, the folding can then proceed in eithersection, or in both sections at the same time. The cylindrical sectioninverts by having the upper edge fold inwardly and the folding continuesdownwardly until the upper edge is in contact with the inside of thelower edge of the cylindrical section.

An undulating or grooved section inverts in a manner similar to that ofthe tapered section 46, as shown in FIG- URE 4. In a grooved wall, thewall will fold in the straight section between the grooves and groove,such as 17, will fold towards and approach the next larger groove 17'.If inadequate clearance is provided between grooves, a groove such as 17can hinder or halt the inverting of the flexible section by restrictingor preventing the downward movement of the smaller groove 17.

In the mixing operation initially one fluid is transferred from acompressed container into a decompressed container where it mixes andcombines with the fluid stored therein, and then subsequently,

the combined fluids are transferred back and forth between the twocontainers in order to obtain a uniform and homogeneous mixture.

The total volume of the fluids within the containers can therefore, ifdesired, be no greater than the maximum internal volume of eithercontainer in order to permit the combined fluids to be completelycontained, alternately by one container and then the other. While thecontainers, and particularly grooved container, are capable of someexpansion due to their resilient construction, in a system, for example,where the fluids are to be mixed in a one to one ratio, slightly lessthan half filling each container with fluid provides for an efficientmixing of the fluids.

The filled containers can be individually sealed for example, throughthe use of separate closure caps for each unit or by a closure securedto the containers 40 and 41, by means of threads 42 and 43 respectively.Alternatively, the units may be sealed one into the other by securingone container 40 to the other container 41 by means of female threads 44and male threads 43, and using a frangible seal across the opening 45 ofone container 41, or by any similar convenient means.

When the fluids are to be mixed, a frangible seal across opening 45 canbe broken by holding the necks of the containers and applying pressureto the end of one container while leaving the other container free toexpand.

Premature breakage of the frangible seal is unlikely during storageinasmuch as the containers resist compression, when a force other thanan axial force is applied, and an axial pressure on the end of onecontainer would normally be resisted by an equal axial force on the endof the other container.

Other combinations of sealing and coupling means can readily be employedfor sealing the containers during storage and providing fluidcommunication during the mixing operation, depending upon therequirements of a particular application.

The containers 10 and 11, and 40 and 41, have been shown mated byscrewing the neck of one container (11 and 41) into the neck of theother container (10 and 40). However, any

tainer 21, large neck such as neck 18, of container 10.

Coupling can also be provided by dimensioning the inner diameter of theneck of container 10 and the outer diameter of the neck of container 11so as to yield a press-fit type of clearance between the two members andsimply forcing the male neck of container 11 into the female neck 18.

While the containers need not be identical in size and configuration,two containers, such as the container 10, of FIGURE arrangement by meansof a conventional type of internally threaded pipe coupler, and duringthe dispensing operation, a spout can be secured to one container bymeans of a threaded connection. The use of containers with dissimilarsized necks has, however, the advantage of precluding the possibility ofsecuring together two containers, each of which contains the same fluid.The use of a tubular coupler has the advantage of not requiring the useof internal grooves, such as 44 of container 40, which can beinconvenient or expensive to form during the container manufacturingoperations.

As a further modification, one or both of the containers 10 and 11 canbe provided with a frangible seal in the same manner as previouslydescribed in regard to container 4. The containers can then be coupledbymeans of a tubular female coupler the seal or seals being broken aspreviously noted, when mixing of the fluids is desired.

When providing both containers with frangible seals, the seals can,advantageously, be simultaneously bro-ken secured together by means ofan elongated tubular female coupler which is of suflicient length tothreadedly engage each container while maintaining the containers in aspaced relationship. The spacing must be adequate to enable the tubularcutting member to be positioned between the seals of the two containers.When the seals are to be broken, the containers are rotated and advancedtowards each other thus decreasing the space between the seals until thecutting member is forced to sever each seal. The cutting member ispreferably provided with small ridges or other similar means, in orderto concentrically position the tubular cutting member within the tubularcoupling member and in order to limit the extent to which the cuttingmember can enter each container,

thus preventing the tubular cutting member from being forced through oneseal and into one container without cutting the other seal.

In the case of containers such as are to be sealed by means of threadedclosure caps or the like, the containers are filled with the properamount of fluid and then sealed. Prior to the mixing operation, eachcontainer can be opened and, if desired, compressed in order to expel aquantity of air from the container, the amount depending upon therelative extensibility of the containers. The two containers are thensecured together, as previously noted, by means of a tubular couplingmember, or by inserting the neck of one container into the neck of theother container, as shown in FIG- URES I and 4.

The filling operation, in the case of containers employing a frangibleseal across the neck of one or both of the containers and which seal orseals can be broken while the containers are coupled together, consistsof properly filling one container, such as container 41, with a firstfluid and displacing air, as desired, by compressing the container. Thefrangible seal is then secured across contalner, as for example, by

10 and 11, which sealed by securing together the two containers 40 and41, by means of a tubular female coupler; or as shown is provided with afrangible seal, in the same manner as container 41 and the containersare coupled together by means of a tubular female coupler.

The mixing operation is initiated by compressing one The neck sectionsof the containers, as shown in FIG- are relatively narrow in comparisonto containers. The neck, thus acts as a restriction and producesturbulent flow, which enables high viscosity as well as low viscosityfluids to be rapidly, uniformly and homogeneously mixed.

The mixed fluids are most conveniently dispersed through the use of adispensing spout 27 which is either as 27 of container 21, the open neck26, is sealed by means of a screw cap in the manner employed for sealingthe containers during the storage period and a frangible seal 28, at thesealed end of the dispensing spout is broken. Thus, the mixed fluids canbe dispensed through the spout 27, as the container 21 is collapsed,either manually or mechanically by means of a conventional gun such asseen in US. Patent 2,838,210 or 3,042,268, suitably adapted to thisshape container.

While the material trapped in the integrally formed spout 27 during themixing operation will usually not interfere with the adequacy of themixing operation, a frangible seal can alternatively be positionedacross the entrance 29 to the spout 27 in order to prevent fluid fromentering the spout.

Although the invention has been described in its preferred forms with acertain degree of particularity, it is understood that the presentdisclosure of the preferred forms has been made only by way of exampleand that numerous changes in the details of construction and thecombination and arrangements of parts may be resorted to withoutdeparting from the spirit and the scope of the invention as hereinafterclaimed.

What is claimed is:

1. An apparatus for use in the storage, mixing and dispensing of fluids,comprising a pair of containers, each container having a first rigidsection and a second flexible section, said first and said secondsections in unitary comb ination forming an enclosed hollow chamber atleast one of said sections of each container having a sealable means foringress and egress of fluid in association therewith, said flexiblesection of each container being toldable within said rigid section ofthe same container, the ingress and egress means of one container, beingin fluid-tight engagement with the ingress and egress means of the othercontainer thereby forming a fluid-tight binary mixing container.

2. An apparatus for mixing fluids within a pair of attached containerscomprising, in combination, a pair of flexible containers, eachcontainer having a first rigid conical section and a second flexibleconical section, said first and second sections in unitary combinationforming a hollow chamber, said second sections having increasingflexibility with increasing distance from the central axis of saidconical section, the interior chambers of said containers being incommunication and forming a fluid-tight binary mixing containerassembly, whereby upon applying pressure to the second, flexible sectionof one container causes the outermost portion of said second section toinitially flex, the flexing continuing radially inward until said secondconical section has substantially entirely inverted, thereby displacingthe fluid from the flexed container.

3. An apparatus for mixing fluids within a pair of attached containerscomprising, in combination, a pair of flexible containers, eachcontainer having a first rigid conical section and a second flexibleconical section, said first and second section in unitary combinationforming a hollow chamber, the walls of said second section havingincreasing flexibility with increasing distance from the central axis ofsaid conical section, one section of each of said sections having acylindrical section at its apex, the cylindrical section of onecontainer being in fluid-tight engagement with the cylindrical member ofthe other container, and the interior chambers of said containers beingin communication and forming a fluid tight binary mixing containerassembly, whereby upon applying pressure to the second flexible sectionof one container causes the outermost portion of said second section toinitially flex, the flexing continuing radially inward until said secondconical section has substantially entirely inverted and contacted saidfirst conical section.

4. The structure of claim 3, wherein said second section has adecreasing wall thickness with increasing distance from the central axisof the cone.

5. The structure of claim 3, wherein said conical sections have vertexangles from about 40 to about and the vertex angle of each of saidflexible sections is slightly less than the vertex angle of said rigidsections.

6. The structure of claim 3, wherein said second sections include seriesof axially spaced grooves.

7. The structure of claim 6, wherein the maximum diameter of each grooveis less than the minimum diameter of the adjacent, larger groove.

8. An apparatus for mixing fluids within a pair of attached containerscomprising, in combination, a pair of flexible containers, eachcontainer having a first rigid conical section and a second flexibleconical section, said first and second sections in unitary combinationforming a hollow chamber, said second section having a decreasing wallthickness and increasing flexibility With increasing distance from thecentral axis of the conical section, one section of each of saidsections having a cylindrical section at its apex, the cylindricalsection of one container having a frangible seal and being influid-tight engagement with the cylindrical section of the othercontainer, and the interior chambers of said containers being incommunication and forming a fluid-tight binary mixture containerassembly, whereby upon applying pressure to the second flexible sectionof one container causes the outermost portion of said second section toinitially flex, the flexing continuing radially inward until said secondconical section has substantially entirely inverted and contacted saidfirst conical section.

References Cited UNITED STATES PATENTS 554,071 2/1896 Matzen '215-112,176,923 10/ 1939 Nitardy. 2,208,744 7/ 1940 Bergerioux. 2,433,80612/1947 Bardin 222-206 2,446,451 8/ 1948 Allen 215-11 2,528,530 11/1950Machleder. 2,702,034 2/ 1955 Walter. 2,753,868 7/1956 Seemar. 2,885,1045/1959 Greenspan. 2,893,547 7/1959 Earl. 2,911,972 11/1959 Elinger 128-216 3,100,045 8/1963 Via.

LOUIS G. MANCENE, Primary Examiner.

1. AN APPARATUS FOR USE IN THE STORAGE, MIXING AND DISPENSING OF FLUIDS,COMPRISING A PAIR OF CONTAINERS, EACH CONTAINER HAVING A FIRST RIGIDSECTION AND A SECOND FLEXIBLE SECTION, SAID FIRST AND SECOND SECTIONS INUNITARY COMBINATION FORMING AN ENCLOSED HOLLOW CHAMBER AT LEAST ONE OFSAID SECTIONS OF EACH CONTAINER HAVING A SEALABLE MEANS FOR INGRESS ANDEGRESS OF FLUID IN ASSOCIATION THEREWITH, SAID FLEXIBLE SECTION OF EACHCONTAINER BEING FOLDABLE WITHIN SAID RIGID SECTION OF THE SAMECONTAINER, THE INGRESS AND